1. Field of the Invention
The method and apparatus for bi-directional communication between analog and digital devices disclosed herein relates generally to communications interfaces between a display driver and a display device. More specifically, but without limitation thereto, the method and apparatus disclosed herein relates to a bi-directional communications interface between a set top box and a television monitor.
2. Description of Related Art
Three video interfaces commonly used between consumer display devices such as video monitors and display drivers are analog signal interfaces, compressed digital signal interfaces, and baseband digital signal interfaces. These interfaces are used to send video signals from a video source, such as a television set top box (STB), to a video sink, such as a television monitor or display (TV). In the compressed digital signal and baseband digital signal interfaces, there is some provision for upstream data communication from the video sink to the video source in addition to the downstream flow of video signals. In the analog signal interface, however, there is generally no mechanism to transmit upstream data from the video sink to the video source. One method used to transmit upstream data from the video sink to the video source is to connect an additional cable between the video sink and the video source.